US780866A - Back-pressure relief-valve. - Google Patents
Back-pressure relief-valve. Download PDFInfo
- Publication number
- US780866A US780866A US21128904A US1904211289A US780866A US 780866 A US780866 A US 780866A US 21128904 A US21128904 A US 21128904A US 1904211289 A US1904211289 A US 1904211289A US 780866 A US780866 A US 780866A
- Authority
- US
- United States
- Prior art keywords
- valve
- piston
- steam
- casing
- seat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25D—PERCUSSIVE TOOLS
- B25D9/00—Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
- B25D9/14—Control devices for the reciprocating piston
- B25D9/16—Valve arrangements therefor
Description
PATENTED JAN. 24, 1905.
' G. A. CUNNINGHAM. BAGK PRESSURE RELIEF VALVE.
APPLICATION rum) Jun 6, 1904.
WITNESSES y INVENTOR 'Cbiiiz JFZL /z @gnihyiamy N ATTORNEYS UNITED STATES,
Patented January 24, 1905.
PATENT OFFICE.
COLIN ALLEN CUNNINGHAM, OF BRAINERD, MINNESOTA.
BACK-PRESSURE RELIEF-VALVE.
SPECIFICATION forming part of Letters Patent No. 780,866, dated January 24, 1905.
" Application filed June 6,1904. Serial No. 211,289.
To all whom, it mmtyoonccrnfl Be it known that I, COLIN ALLEN CUNNING- HAM, a citizen of the United States, and a resident of Brainerd, in the county of Crow Wing and State of Minnesota, have invented a new and Improved Back-Pressure Relief-Valve, of
which the following is a full,'clear, and exact to completely relieve the piston in the steamcylinder of all pressure over and above steamvchest pressure, thus insuring a steady running of the engine and utilization of the motive agent to the fullest advantage and relieving the piston of all pressure when the engine is drifting. I
The invention consists of novel features and parts and combinations of thesame, as will be more fully described hereinafter and then pointed out in the claims.
A practical embodiment'of the invention is represented in the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.
Figure 1 is a sectional side elevation of the improvement as applied to one end of the engine-cylinder and steam-chest. Fig. 2 is a sectional plan view of the improvement on the line 2 2 of Fig. 1. Fig. 3 is a sectional side elevation of the improvement provided with a cushioning-valve in the outlet, and Fig. 4
is a sectional plan view of the same on the line 44:0f Fig. 3.
On each end of the cylinder A of the locomotive steam-engine is externally secured an elbow B, on which is screwed orotherwise fastened a casing C, preferably made in three parts C, G and C of which the upper part 0 is closed by a screw-cap O and the lower 7 part O is secured to the elbow B. The lower part C of the casing is provided with a valveseat O 'on which is adapted tobe seated the valve D of a piston-valve D, having its piston D fitted snugly in the upper part 0 of the casing O, as plainly shown in Fig. 1. On the under side of the piston-valve D presses a spring E to normally hold the piston-valve D or outlets O leading to the outer air.
in an uppermost position with the valve D off the seat 0 to establish communication between the middlepart O of the casing, which middle part is provided with one or more ports Thus when the engine is drifting at the time the locomotive, say, is running down a hill,- then the piston in the cylinder A is prevented from pumping and compressing air, as each end of the cylinder is open to the atmosphere by way of therelief-valve, as described. v
The cap (J of the casing O is connected by a pipe F with the interior of the steam-chest G, so that the steam-chest'pressure is on the .top of the piston-valve D, and consequently presses the piston-valve D downward, so as to holdthe valve D on its seat while the engine is running; but when the piston in the cylinder A nears its end stroke and creates a pressure above that in the steam-chest G then this preponderance of pressure acts on the under side of the valve D to lift the piston- .valve, so as to open the valve-seat O to allow the preponderance of pressure to pass to the atmosphere by way of the open valve-seat O and the outlets O As soon as the pressure in the cylinder is reduced to that of the livesteam pressure in the steam-chest G then the piston-valve is again forced downward and the valve D moves to its seat O and the spring E is compressed.
If desired, a cushioning-valve H may be employed, and in this case the valve-casing H of the cushioning-valve H is provided with a single outlet O, registering with the space between the valve D and the piston D of the piston-valve D. The valve-casing H is provided with a valve-seat H on which is seated an outwardly-opening valve H normally held to its seat by a spring H arranged in the valve-casing H, opening with its outer end to the atmosphere. It is understood that valve D is held off its seat by the action of the spring E, I provide the valve H with a central port H leading to the outer air, so that air can pass into the part C of the casing even when the valve H is closed.
It is understood that when the steam is shut off from the engine the spring E immediately pushes the piston-valve D upward to move the valve D ofl its seat and to hold it off its seat until steam is again admitted to the steam-chest. By the arrangement described the piston-valve D is prevented from flopping, and a direct connection is had from the cylinder to the atmosphere. By the use of the cushioning-valve H the piston is prevented from pumping much air into the cylinder, and by having the port H in the said valve a vacuum is avoided in the part C and the piston-valve D is hence prevented from being drawn to its seat. The tension of the spring E is such as to compensate for the increase in area of the piston D over the valve D, so that the-piston-valve is moved upward by the spring E and the valve D is moved off its seat 0 as soon as the pressure in the cylinder rises above that in the steam-chest Gr.
Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. Aback-pressure relief-valve, comprising a casing connected at one end with the interior of the steam-cylinder and at the other end With the steam-chest, the casing having a valveseat at the end connected with the steam-cylinder and an outlet intermediate of its ends, said outlet leading to the atmosphere, and a piston-valve in the said casing, the valve of the piston-valve being adapted to be seated on the valve-seat and the piston being of a larger area than the piston-valve, and means for holding the valve from its seat when the piston is relieved of steam-chest pressure, whereby the cylinder is placed in communication with the atmosphere when the engine is drifting.
2. A back-pressure relief-valve, comprising a casing connected at one end with the interior of the steam-cylinder and at the other end with the steam-chest, the casing having a val veseat for connection with the steam cylinder and an outlet leading to the atmosphere, a piston-valve in the said casing, the valve of the piston-valve being adapted to be seated on the valve-seat and the piston being of a larger area than the piston-valve, and the said outlet beingintermediate the piston and the valve when thelatteris seated and the pressure from the steam-chest is on the piston, and a spring pressing the piston-valve to move and hold the valve off its seat when the piston is relieved of steam-chest pressure.
3. Abaek-pressurerelief-valve, comprising a casing connected at one end with the interior of the steam-cylinder and at the other end with the steam-chest,the casing having a val veseat for connection with the steam-cyliinler and an outlet leading to the atmosphere, a piston-valve in the said casing, the valve of the piston-valve being adapted to be seated on the valve-seat and the piston being of a larger area than the piston-valve and the said outlet being intermediate the piston and the valve when the latter is seated and the pressure from the steam-chest is on the piston, a spring pressing the piston-valve to move the valve off its seat, and a cushioning-valve in the said outlet.
4:. A back-pressure relief-valve, comprising a casing connected at one end with the interior of the steam-cylinder and at the other end with the steam-chest, the casing having a valveseat for connection with the steam-cylimler and an outlet leading to the atmosphere, a piston-valve in the said casing, the valve of the piston-valve being adapted to be seated on the valve-seat and the piston being of a larger area than the piston-valve and the said outlet being intermediate the piston and the valve when the latter is seated and the pressure from the steam-chest is on the piston, a s1 )ring pressing the piston-valve to move the valve off its seat, and a cushioning-valve in the said outlet, having a central port open at all times.
In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.
COLIN ALLEN CUNNINGHAM. itnesses:
R. G. VALLENTYNE, JNO. N. NEVERS.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US21128904A US780866A (en) | 1904-06-06 | 1904-06-06 | Back-pressure relief-valve. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US21128904A US780866A (en) | 1904-06-06 | 1904-06-06 | Back-pressure relief-valve. |
Publications (1)
Publication Number | Publication Date |
---|---|
US780866A true US780866A (en) | 1905-01-24 |
Family
ID=2849350
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US21128904A Expired - Lifetime US780866A (en) | 1904-06-06 | 1904-06-06 | Back-pressure relief-valve. |
Country Status (1)
Country | Link |
---|---|
US (1) | US780866A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2544793A (en) * | 1948-02-20 | 1951-03-13 | Edmund P Kelly | Automatic drifting valve |
-
1904
- 1904-06-06 US US21128904A patent/US780866A/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2544793A (en) * | 1948-02-20 | 1951-03-13 | Edmund P Kelly | Automatic drifting valve |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US780866A (en) | Back-pressure relief-valve. | |
US2230718A (en) | Valve | |
US1965070A (en) | Air compressor governor | |
US741828A (en) | Cylinder relief-valve. | |
US820239A (en) | Valve. | |
US933147A (en) | Cylinder relief-valve. | |
US557515A (en) | Air-brake | |
US328979A (en) | Check-valve | |
US121283A (en) | Improvement in locomotives | |
US686779A (en) | Relief-governor for air-compressors. | |
US1212951A (en) | Relief-valve for compressor systems. | |
US458845A (en) | Relief-valve for steam-cylinders | |
US141343A (en) | Improvement in steam-engines | |
US747538A (en) | Back-pressure relief-valve. | |
US654771A (en) | Valve mechanism. | |
US674808A (en) | Automatic governor for fluid-compressors. | |
US795134A (en) | Cylinder drainage and relief valve. | |
US625118A (en) | Automatic throttle-valve | |
US581790A (en) | Safety-valve | |
US442492A (en) | Craven r | |
US737294A (en) | Steam-engine. | |
US714345A (en) | Combined vacuum relief-valve. | |
US712009A (en) | Reducing-valve. | |
US730682A (en) | Governing device for steam-pumps. | |
US401915A (en) | Automatic pump-governor for brake mechanisms |